Computerized drive mechanism for exercise, physical therapy and rehabilitation

Exercise apparatus comprising:

• a supporting structure;
• a flexible tension transmitting device supported by said supporting structure;
• said flexible tension transmitting device being linearly extendable and retractable;
• a user force application device operatively connected to said flexible tension transmitting device for transmitting user force tending to extend said tension transmitting device;
• a linear actuator including a hydraulic cylinder having a piston slideably supported therein dividing said cylinder into first and second variable volume chambers;
• a piston rod having one end connected to said piston and the other end operatively connected to said flexible tension transmitting device;
• a first hydraulic fluid line connected to said first variable volume chamber and a second hydraulic fluid line connected to said second variable volume chamber;
• a proportional flow control valve connectable to control the flow rate through said first hydraulic fluid line when hydraulic fluid is being expelled from said variable volume chamber, and through said second hydraulic fluid line when hydraulic fluid is being expelled from said second variable volume chamber;
• a pump supplying said hydraulic fluid through said second hydraulic fluid line to said second variable volume chamber when said hydraulic fluid is being expelled from said first variable volume chamber, and through said first hydraulic fluid line to said first variable volume chamber when said hydraulic fluid is being expelled from said second variable volume chamber;
• a load cell positioned to measure said user force applied to said user force application device and producing signals representative of said user force applied;
• a computer connected to said load cell to receive said signals and to produce display control signals representing the instantaneous force being applied at said user force application device;
• a display connected to said computer to receive said display control signals and to display a corresponding force image.

Exercise apparatus for providing isokinetic concentric and eccentric exercise comprising:

• a supporting structure;
• control means including a power driven linear actuator having an extendable and retractable shaft mounted on said supporting structure;
• a flexible tension transmitting device having one end connected to said shaft and the other end connected to user force application device;
• said user force application device having an initial position and an extended position constituting an origin;
• said control means limiting movement by a user of said user force application device from said initial position only at a first fixed velocity through at least a portion of the distance to said extended position;
• said control means driving said user force application device through said flexible tension transmitting device back to said initial position at a second fixed velocity by exerting a force in excess of a resisting force applied by the user.

A method of inducing preferred user exercising techniques with apparatus having a reciprocatable flexible tension transmitting device having a first end and a second end with a user force application device connected to the first end comprising the steps of:

• (1) connecting the second end of the reciprocatable flexible tension transmitting device to a linear actuator;
• (2) restricting extension of said reciprocatable flexible tension transmitting device to a first constant velocity;
• (3) retracting said reciprocatable flexible tension transmitting device at a second constant velocity;
• (4) simultaneously with steps 2 and 3, displaying to a user a first image representing force presently being exerted by the user on the user force application device, and a second image representing force exerted by the user on the user force application device on a previous occasion.